The Quantum Program Dependence Graph and its uses in Quantum Software Development

Quantum software is increasingly recognized as a critical component of quantum computing systems. As resources for quantum software design grow, the need for specialized tools and techniques to support quantum software development becomes more pressing. In this paper, we introduce the quantum program dependence graph (QPDG), a novel dependence analysis model specifically tailored for quantum software. The QPDG operates directly on the source code of quantum programs, capturing both classical and quantum-specific dependencies—namely, entanglement, no-cloning, temporal, and measurement dependencies—thus providing detailed insights into program dependencies at the code level. We further discuss key applications of QPDG, including quantum program slicing, comprehension, debugging, testing, maintenance, reuse, and complexity metrics, demonstrating its potential to enhance various aspects of quantum software engineering.